Bone grafting is a surgical procedure for repairing bones and typically involves introducing a mixture of particulate, such as bone graft material, into an area of bone that requires repair, such as a fracture. The bone graft material is intended to stimulate growth of healthy native bone tissue, and new native bone tissue may eventually replace the bone graft material completely. Bone graft material is a type of biomaterial and typically includes a combination of crushed bone and a liquid component, such as blood, plasma, or growth factors. Bone graft materials can be allograft (derived from a human other than the one receiving the graft), autograft (derived from the human receiving the graft), and synthetic (created from, for example, ceramics like calcium phosphates).
Bone graft materials are typically delivered to a surgical site using syringe-like delivery devices, which often include attachments, such as small diameter cannulae. In addition, the components of the bone graft material are sometimes brought together and combined to form the mixture of the bone graft material in the delivery device. However, the mixture of the bone graft material tends to also include gas from the porosity of the crushed bone and the aeration associated with mixing the components. As the bone graft materials dry after being applied to the surgical site, a portion of the gas collects into pockets within the setting bone graft material. The pockets create inconsistencies in the final bone graft material that may result in performance variation throughout the bone graft material.
Furthermore, hydrating the particulate biomaterial with the liquid biomaterial requires additional time for the liquid biomaterial to displace the gas and disperse throughout the entirety of the particulate biomaterial. At the very least, this additional time increases the cost of the medical procedure. In addition, a relatively fine particulate biomaterial tends to non-uniformly absorb the liquid component, which requires additional blending to mix the particulate and liquid biomaterial to a generally uniform mixture.
There is a need for an apparatus and method for hydrating a particulate biomaterial with a liquid biomaterial, such as a particulate and liquid bone graft materials, that reduces the gas within the mixture and addresses present challenges and characteristics such as those discussed above.